Engine-lathe.



' G. c. GARDNER 11. A. GROW.

ENGINE LATHE.

' APPLICATION FILED lAN.6, 1915. 1,139,026. Patented May11,1915.

3 SHEETS-SHEET I.

G. C. GARDNER & J. A. GROW.

ENGINE LATHE.

APPLICATION FILED JAN. 6. 1915] Patented May 11, 1915.

3 SHEETSSHEET 2.

G. C. GARDNER & J. A. GROW! ENGINE LATHE APPLICATION HLED lAN.6.19l5.

- Patented May 11, 1915.

1,139,026 a s EET T 3 fillllllllll -uw/1/II//wm x UNITED STATES PATENT OF FIOE.

GEORGE C. GARDNER AND JAMES A. GROW, OF RICHMOND, VIRGINIA, ASSIGNORS TO THE TBEDEGAB. COMPANY, OF RICHMOND, VIRGINIA, A CORPORATION OF VIR- GINIA.

ENGINE-LATHE.

Patented May 11,1915.

Application filed January 6, 1915. Serial No. 851.

To all whom it may concern:

Be it known that we, GEORGE C. GARDNER and JAMES A. GROW, both citizens of the United States, residing at Richmond, in the county of Henrico and State of Virginia, have invented certain new and useful Improvements in Engine-Lathes, of which the following is a specification.

Our invention relates more particularly toat-tachments for engine lathes, but in or der that our improvements may be fully understood we have shown in the accompanying drawings parts of an engine lathe of ordinary construction, slightly modified, and with our improvements applied.

Our invention relates particularly to engine lathes of the class in which the work is carried by the rotary member of a headstock and the tool, is attached to a toolholder mounted on a support in turn mounted on a carriage which is movable longitudinally of the lat-he. and in which lathe while the tool-holder does not rotate it is fed with the carriage towardvthe work at the required speed. I

Heretofore the longitudinal movement of the tool-holder toward and from the work has generally been effected by moving the tool-carriage to which the tool is rigidly secured toward and, from the head-stock either by means of a pinion on the carriage engaging a rack on the 'lathe-bed or by a nut 0n the carriage engaging a longitudinal lead screw.

According to our invention we provide a lathe which may be operated and adjusted in the usual way and in Which also provision is made bv means of which the feed or longitudinal movement of the tool-carriage may be effected by. moving the carriage and tool-holder by-mcans of the lead screw and certain novel connections between the lead screw and the tool-holder, in which case of the connections between the lead screw and our improved attachment. Fig. 3 is a detail view, in section, and on an enlarged scale, showing the mechanism for moving the carriage longitudinally on the lathebed by means of rack and pinion mechanism. Fig. l is a detail view, on an enlarged scale and in longitudinal section, showing particularly part of the mechanism connecting the tool-holder with the lead screw. Fig. 5 is a view on an enlarged scale, and in rear end elevation, of the lathe shown in Fig. 1, the lead screw being shown in transverse section. Figs. 6 and 7 are also on an enlarged scale. Fig. v6 shows an end elevation of the hand-wheel for operating the half nuts, which latter are shown in dotted lines. Fig. 7 is a detail view in section, showing more particularly the connections between the hand-wheel and the half nuts. Fig. 8 is a detail view, on an enlarged scale, and in side section, showing how our improvements may be applied to a turret lathe. Fig. 9 shows a plan view thereof. Fig. 10 is a detail view in section, showing the connections between the screw, forming part of our invention, and the tool-holder or boring bar. Fig. 11 is a'detail view, showing other features of such connection. Fig. 12 illustrates another way of connecting said screw with the boring bar or toolholder. Fig. 13 is a detail view, partly in side elevation and partly in section; showing a thrust hearing which is applied to the head-stock of the lathe.

As before stated, our invention contemplates very little change in the lathe proper, I

but in order that our improvements may be-fully understood we-will describe in a general way the general characteristics-of the lathe shown and will indicate how our improvements are applied thereto and used in connection therewith.

The lathe-bed A supports the head-stock and the tail-stock in the usual way. B indicates the rotary part of the head-stock andto this rotary part B the work X is attached in the usual way. C indicates a sup ort for the work which is also of usual construction.

The lathe-carriage D may be provi e with the usual mechanism for adjustingit, and a pinion E is adapted to engage a longitudinal rack F on the lathe-bed, which pinionmay be operated either by hand or by ed by a hand-wheel E ('Fig. 1). The hub of the wheel E is connected with the stem 6 by a feather, as shown, and a spring detent e is adapted to engage recesses .e, e in the stem. By this means the pinion E may be moved into and out of engagement with the rack F and held in either the engaged or disengaged position. All of such mechanism is of usual construction. 1 G indicates the usual lead screw, operated in the usual way. to feed the carriage withthe tool thereon toward and from the work. We have indicated at G the mechanism for connecting and disconnecting the lead Screw with the carriage. The tool-holder H (which is also called the boring bar) is mounted on a suitable support H on the tool-carriage.

between the support H and the tool-holder. As shown the reduce tool-holder lies in a block b, forming part of the'support H, and said tool-holder is rigidly connected with said support by a cap h which is bolted down to the supportl Preferably the cap is connected with the tool-holder by groove-and-feather connection k which will prevent the tool-holder from turning about its axis while at work. It will be understood, however, that there is no longitudinal movement of the tooLholder relatively to its support H. a

To the rear end of the tool-holder H is connected a screw I which extends into the tail-stock B of the lathe and through a sleeve J, having a shoulder j which rests against the tail stock a'nd provides the rearend thrust bearing of the mechanism. This sleeve J forms a bearing support for the rear portion of the screw I and this screw also extends through a sleeve K to which is keyed at k a 'Worm wheel L. between which and the sleeve J is interposed a bearing collar M.

N indicates an annular hand-wheel surrounding the screw I andreceiving a collar.

0 on which the hand-wheel is free to rotate. Between the hand-wheel and collar and the sleeve K are interposed half nuts P which are pivoted on rods Q, shouldered at g, g

and tapped into the sleeve K. These rods extend through the collar' oand carry nuts q. By reasonof the shoulders g, 9' the hand-wheel and collar are held a sufficient distance from the sleeve K to nuts to move freely.

The worm-wheel L engages a worm r on A rigid connection is maderear portion of the allow the half an inclined shaft R mounted in suitable hearings on a frame S. The lower end of the shaft R carries a worm-wheel T which engages a worm T keyed to the lead screw G, as indicated particularly in Fig. 2.

and

has two bearings brackets 1", 1" at i'ts"up-.

per end. The shaft I has a left-hand screw and the arrangement is such that the thrust on the shaft R is downward, causing the worm-wheel r to bearagainst the lower bracket 1'. which is firmly secured to the frame S.

In order that the half nuts P shall properly engage the screw I, they should be threaded, as shown in Fig. 4, and should en'-' gage the screw as there shown. This, however, cannot be effected unless the threads in the nuts are properly positioned to receive the threads of the screw, and in order that this may be accomplished the connection'between the frontend of the screw I and the tool-holder is made adjustable, in the manner indicated,particularly in Figs. 10 and 11. As there shown the screw I extends into a recess in the rear end of the tool-holder and it is provided with an annular roove i, into which projects a pin z" carried by the tool-holder. This arrangement permits the screw to revolve or turn relatively to thetool-holder but prevents its endwise withdrawal therefrom.

1' indicates a hand-wheel which is con nected to the screw by a key i, so that whenthe hand-wheel is turned the screw is also turned.

2' indicates a spring pawl carried bythe hub of'the hand-wheel and which is adapted to engage recesses a2 formed in the end of the tool-holder. The arrangement is such that when the wheel I is turned in one direction the pawl engages one of the recesses and the wheel, screw and tool-holder are locked together, but if the wheel I be turned in the -municated to the SlQBWi K collar.

of connecting the screw shaft I with the tool-holder. Instead of forming the recesses a: in the tool-holder and instead of boring the tool-holder to receive the end of the shaft, we provide a sleeve I which is threaded at b and engages a thread I) cuton the reduced rear end of the tool-holder. Recesses w are cut into the rear or outer end of the sleeve I of the wheel I. The screw shaft is formed at its front end with a head I) which is adapted to enter the sleeve I and bear against the shoulders I) thereof. As before stated the end thrust at the tail-stock is taken by the bearing collar M inasmuch as the rearward thrust of the spindle I is comthrough the nuts P and the worm Wheel L bears againstsaid In order to take the end thrust at the head-stock we preferably equip the latter with the devices shown in Fig. 13. In this figure U indicates a part of the frame of the head-stock and V indicates a sleeve forming part of the rotary portion of the head-stock. This sleeve V, shown in .Fig. 13, is also indicated in Fig. 1. A bearing block V is supported on a suitable frame W attached to the frame U and this bearing block receives a ball in attached to the sleeve V. By this mechanism, when the operation of boring is being performed the end thrust is received at both ends of the lathe in such manner as to take the strain from other portions thereof. \Vhen the half nuts P are disengaged from the screw I the carriage D may be moved back and forth longitudinally by means of the pinion E. This may be readily disengaged, when the desired adjustment is given to the carriage and then the lead screw G may be connected with the carriage by means of the devices G and the lathe may then be operated in the usual way as in other lathes, the carriage being equipped with a suitable toolholder. But when the half nuts are made to engage the screw I the latter will operate in the manner before described in accordance with our invention. It will thus be understood that the carriage may be adjusted and fed back and forth by means of the rack and pinion mechanism and by means of the lead screw, or these may be thrown out of operation and the carriage and tool-holder may be operated or fed toward the work in accordance with our invention.

Our invention is especially useful for rough boring cast iron or bar stock steel to convert it into bushing form. Finer boring may be effected by other mechanism.

Our improvements may be applied to a turret lathe in the manner indicated in Figs. 8 and 9. As there shown the circular top plate Y of the turret is pivotally connected with supporting blocks Y, 'Y' by means of a pivot bolt To this pivot bo t is conto receive the spring ,pawl i bring either nected a castin 3 in turn connected with the screw shaft%, hereinbefore referred to.

H indicates a tool-holder or boring bar of the kind hereinbefore described.

it indicates lubricating devices therefor. The tool-holder is supported in a frame A which also carries an adjustable tool-holder a. The arrangement is such that the cir cular top plate Y may be turned so as to the tool holder H or tool-holder a into line with the work. In either case the projection y of the casting 3 will bear against the tool-holder and feed it toward the work.

We claim as our invention:

prising a supporting frame, a shaft carried thereby and provided with means for connecting it with the lead screw of the lathe, a screw shaft adapted to be connected with the tool-holder of the lath, and connections between said first-mentioned shaft and said screw shaft.

2. An attachment for engine lathes, comprising a supporting frame, a shaft carried thereby and provided with means for operatively connecting it with the lead screw of the lathe, a screw shaft adapted to be connected with the tool-holder of the lathe, a sleeve surrounding said screw shaft and geared to said first-mentioned shaft, half nuts engaging said screw shaft, and a handwheel connected with said half nuts for opening and closing them.

3. An attachment for engine lathes, comprising a supporting frame, a shaft carried thereby and provided with means for operatively connecting it with the lead screw of the lathe, a screw shaft ada ted to be connected with the tool-holder o the lathe, a hand-wheel carried by said screw shaft and provided with a pawl adapted to engage the tool-holder, and connections between said first-mentioned shaft and said screw shaft.

4. The combination with the head-stock and tailstock of an engine lathe of a. rotary spindle adapted to be connected with the work, an end thrust bearing for said spindle, a tool-holder or boring bar supported on the lathe carriage, a screw shaft connected with said boring bar and extending into the tail-stock, a sleeve surroundin said screw shaft and carrying a worm whee an end thrust bearing interposed between the tail-stock and said sleeve and worm wheel, means for connecting said sleeve with the screw shaft and for disconnecting it therefrom, and connections between said Worm wheel and the lead screw of the lathe.

5. An engine lathe, comprising a carriage, a rack, and a lead screw, means for connecting the carriage with the lead screw and for disconnecting it therefrom, a pinion mounted on the carriage and'adapted to becon- 1. An attachment for engine lathcs, comnected with the rack and to be disconnected therefrom, a tool-holder, a support on the carriage to which the tool-holder is secured, a screw shaft connected with the tool-holder and extending into the tail-stock of the lathe, driving connections between said screw shaft and the lead screw of the lathe, and means for connecting the screw shaft with said driving connections and for disconnecting it therefrom,

6. The combination in an engine lathe of a tool-holder, a lead screw, a carriage, means for connecting the carriage with the lead screw and for disconnecting it therefrom, a

screw shaft, driving connections between the screw shaft and the lead screw, a hand-wheel on the screw shaft, and means carried by the hand-wheel for connecting it with the toolholder to hold the screw shaft against rotation relatively to the tool-holder.

In testimony whereof, we have hereunto subscribed our names.

GEORGE C. GARDNER. JAMES A. GROW.

Witnesses:

E. 'W. COOPER, OA'IESBY AP C. JONES. 

